克雷白氏杆菌(Klebsiella pneumoniae Tzyx1)降解对羟基苯甲酸的调控基因及降解途径分析

Regulatory Genes of p-Hydroxybenzoic Acid Degradation by Klebsiella pneumoniae Tzyx1 and Its Degradation Pathway

以对羟基苯甲酸为唯一碳源,采用平板划线法从某印染废水中筛选获得一株高效对羟基苯甲酸降解菌株,对其菌株形态及生理生化特性进行分析,鉴定为克雷白氏杆菌(Klebsiella pneumoniae),命名为K.pneumoniae Tzyx1;用cDNA文库构建的方法分别对纯培养和对羟基苯甲酸胁迫的K.pneumoniae Tzyx1基因进行分析和比较,查找其降解对羟基苯甲酸的调控基因并推测降解途径。结果表明,有8个调控基因直接与对羟基苯甲酸的降解有关,K.pneumoniae Tzyx1降解对羟基苯甲酸可通过原儿茶酸代谢途径实现。为进一步研究克雷白氏杆菌降解对羟基苯甲酸的分子机制奠定了基础。

Using p-hydroxybenzoic acid as a sole carbon source,we isolated a high-efficient p-hydroxybenzoic acid degradation strain from printing and dyeing wastewater by a plate streak method.Moreover,we analyzed the morphological and physiological and biochemical characteristics,identified the strain as Klebsiella pneumoniae and named as K.pneumoniae Tzyx1.Furthermore,we analyzed and compared the genes of K.pneumoniae Tzyx1 cultured in glucose medium and p-hydroxybenzoic acid medium using the method of cDNA library establishment,searched for regulatory genes and predicted degradation pathway.The results show that 8 regulatory genes are directly related to the degradation of p-hydroxybenzoic acid,and the degradation of p-hydroxybenzoic acid by K.pneumoniae Tzyx1 can be achieved through the procatechuic acid metabolic pathway.This study lays a foundation for the further research on the molecular mechanism of degradation of p-hydroxybenzoic acid by K.pneumoniae.